That set Rayan up perfectly for a sensational breakout year. On January 20, 2023, the Brazilian attacker became the youngest player to feature for Vasco's senior team in the 21st century when coming off the bench in a 1-1 draw against Audax in the Campeonato Carioca, at the age of 16 years and 170 days.
He would go on to make more history at club level, but first jetted off to the South American Championship in Ecuador with Brazil's U17 squad. The Selecao stormed to the title, winning eight of their games and drawing just one, and Rayan won a share of the Golden Boot with five goals, alongside team-mate Kaua Elias and Argentina's Claudio Echeverri (now on the books of Manchester City).
Rayan returned to Vasco full of confidence and broke another one of the club's 21st-century records after being handed his first start in a league clash with Internacional in June, this time for youngest goal-scorer. Vasco lost the game 2-1, but Rayan bagged most of the headlines with his close-range finish, which also made him the fourth-youngest scorer ever in the Brasilerao, behind current Real Madrid starlet Endrick and former Brazil national team duo Jo and Anderson, who enjoyed spells at Manchester City and Manchester United, respectively.
That was the only goal Rayan scored in the 2023 campaign from six Serie A appearances, but he featured in 24 games the following season as he became a regular off the bench. His standout moment came in a clash against Criciuma, in which he produced a fine first-time strike to put Vasco 2-1 up before the break, only for the home side to snatch a point right at the death.
Rayan also played a key role in Vasco's run to the semi-finals of the Copa do Brazil, before getting himself sent off in the first leg of their tie against Atletico Mineiro. Vasco eventually lost that game 2-1 and could only get a draw in the second leg, but no one pointed the finger at blame at Rayan and it didn't detract from what was otherwise another impressive year for the youngster as he learned from the experience to reach a far higher level.